Scanners are used to obtain a copy of an original image. The digital image file can be stored, processed and/or printed. To obtain an accurate copy of the original, scanners need to be able to scan so that the colors of the scanned file should be close or identical to the original.
A known type of scanner is a CIS (Contact Image Sensor) scanner, wherein the image sensor scans the original at a close distance from the original to obtain an accurate image. CIS scanners are usually provided with a linear array of red, green and blue LEDs (Light Emitting Diodes) for shining light onto the original and an image sensor for recording the image, as reflected by the original.
Particular scanners use a CCD (Charged Couple Device) or CMOS (Complementary Metal Oxide Semiconductor) type image sensor. These sensor types are sometimes used in older and/or more expensive scanners. CCD and CMOS type scanners are known to obtain higher color accuracy and/or a higher resolution than CIS scanners. However, these types of scanners are expensive and space inefficient as compared to the CIS type scanners.
At the end of the manufacturing stage, and during the lifetime of the scanner, color charts can be used to calibrate the scanner. By regularly calibrating the scanner, a high color accuracy of the scanner may be maintained or obtained. To enhance color accuracy, scanners and scanner software oftentimes allow for pre-selection of the type of original image, such as photo or text. Also, color tuning may be applied after scanning to improve the color accuracy of the obtained image file.